The Vallée de la Marne runs west from Épernay along both banks of the river towards Château-Thierry, and it is the largest of the Champagne subregions by area. The slopes are clay, marl and sand over the chalk rather than chalk itself, heavier and colder than the Côte des Blancs, and the valley floor is a frost trap, which is why the vines are planted on the flanks.

Those conditions suit Meunier, which buds late and ripens early, and the valley holds most of the Meunier in Champagne. It gives soft, fruity, early maturing wine that fills out a blend and is the backbone of a great many non vintage bottles. The abbey at Hautvillers, where Dom Pierre Pérignon was cellarer from 1668, stands on the hillside above the river, and the villages strung along the valley, Aÿ, Mareuil-sur-Aÿ, Cumières and Damery among them, include some of the oldest names in the region.